Wire wrapping tool



Nov. 23, 1965 J. MEYER 3,

q M WIRE WRAPPING TOOL Filed July 9, 1962 2 Sheets-Sheet 1 INVENTOR.

JOHN L. MEYER BY ATTORNEY Nov. 23, 1965 J. L. MEYER 3,219,067

WIRE WRAPPING TOOL Filed July 9, 1962 2 Sheets-Sheet 2 I NVENTOR.

JOHN L. MEYER BY w ATTORNEY United States Patent 3,219,067 WIRE WRAPPING TOOL John L. Meyer, Robinson Township, Ottawa County,

Mich., assignor to Gardner-Denver Company, a corporation of Delaware Filed July 9, 1962, Ser. No. 208,337 6 Claims. (Cl. 140-124) The present invention relates generally to tools effective for making a connection between a wire and an electrical terminal by wrapping the wire in successive convolutions about and in intimate engagement with the terminal.

Tools of the aforedescribed general character conventionally include a rotary driver for rotating a bit which is disposed within a sleeve member, the bit being provided at its forward end with a longitudinal recess for the reception of the terminal and with a radially offset longitudinal groove for the reception of the wire. In the operation of the tool, the bit is rotated and the wire is withdrawn from the groove as it is applied to the terminal. Typically, the rotary drivers for the tools comprise motors actuated either by pressure fluid by electricity With either of these types of motor power supply, operator movement from an assigned working area is limited to the available length of the tool power supply line and by the availability of power supply outlets at alternate locations.

An object of this invention is to provide a hand-held tool of the type under consideration which may be easily transported from place to place and having a self-contained power supply thereby permitting use of the tool at locations remote from fixed power supplies. According to the present invention, this object is accomplished by providing a wire-wrapping tool having an electrically operated drive motor supplied by storage battery means attached to and comprising a handle part of the tool.

In order that the tool be as light and portable as possible, the drive motor and battery means are necessarily limited in size and weight and, accordingly, the available driving torque from the motor is somewhat limited. Due to these limitations on weight, size, and available operating power, it is essential that the components of the tool, particularly the motor driven members, be as small and as lightweight as practical. Therefore, another object of this invention is to provide a tool of the type under consideration wherein the number of parts and the size and weight of the parts are substantially reduced in comparison with conventional wire-wrapping tools.

Wire-wrapping tools of the type under consideration are intended to perform highly repetitious operations wherein the tool operator manually inserts a wire in the aforementioned ofrset groove located at the remote end of the wrapping bit. To attain maximum speed and proficiency in the use of these tools, the operator must be able to locate the wire-receiving groove without visual assistance; therefore, after each operation, it is essential that the wrapping bit be indexed to place the groove in a predetermined angular position known to the operator.

In keeping with the aforestated objectives, an important feature of this invention is the provision of a bit indexing mechanism which is simple and lightweight in construction and is operationally particularly well suited for coaction with a miniature battery-powered rotary drive motor.

These and other more detailed objects and advantages will be apparent from reading the following specification and claims and considering in connection therewith the attached drawings, in which:

FIG. 1 is a top plan view of a hand-held wire-wrapping tool embodying the present invention;

FIG. 2 is a side elevational view of the tool shown in operating relation with an electrical terminal;

FIG. 3 is an enlarged end view of a wrapping bit adapted for use with the tool shown in FIGS. 1 and 2;

3,219,067 Patented Nov. 23, 1965 FIG. 4 is a fragmentary sectional view taken substantially along lines 4-4 of FIG. 1;

FIG. 5 is a view taken substantially along lines 5-5 of FIG. 6;

FIG. 6 is a view taken substantially along lines 6-6 of FIG. 4; and

FIG. 7 is a fragmentary exploded isometric view showing parts of the tool indexing mechanism in spaced apart relation.

In the drawings, the numeral '10 generally indicates a casing for a tool constructed in accordance with the present invention. The casing comprises a pair of reversely turned mating halves 10a-10b which preferably are molded from a suitably strong and lightweight plastic material. As shown in FIG. 2, spaced fasteners 12 releasably secure the casing halves 10a-10b in assembled relation. The casing 10 is provided with a hollow depending portion 14 which receives and removably retains a battery pack comprising a generally cylindrical housing 16 for one or more batteries, not shown, disposed therein for a purpose to be described. The depending casing portion 14 and the battery housing 16 provide a convenient handle for manual gripping by a tool operator. A digitally operated trigger 18 for actuating a motor switch 19 is mounted for limited pivotal movement within an opening at the front of the tool.

A stepped nose portion 22 of casing 10 houses a rotary indexing mechanism generally indicated by numeral 24. Extending forwardly from the front of nose portion 22 is a collet 26 which threadedly cooperates with a collet nut 28 for releasably retaining a sleeve 30 in surrounding relation with a conventional wire wrapping bit 32. In a manner to be described, the bit 32 is rotatably driven by the present tool to wrap or coil a wire 34 about a terminal 36 in helical convolutions to provide an electrical connection therebetween.

Disposed within the cavity defined between the housing halves 10a-10b are a rotary driver 38 and the aforementioned indexing mechanism 24. Preferably, the rotary driver for the present tool comprises a battery-powered electric motor 38 of the type employed as driving means for electric shavers and the like. conventionally, this type of motor is capable of free inertial rotation after deenergization and has little or no resistance to retrograde rotation. The structural and operational features of these motors are well known and need not be described herein in detail. The motor 38 is supported within casing 10 by engaging portions of the casing and by a bearing plate 40 which seatably receives a bearing 42 for the moto'f shaft 44. The motor shaft 44 extends forwardly through an opening in the bearing plate 40 and carries a pinion gear 46 which meshes in driving relation with a spur gear 48 that is integrally formed about a rotary spindle 50. The opposite ends of spindle 50 are supported and rotatably journaled respectively by a bearing 52, mounted in an opening in the bearing plate 40, and by a collet bushing 54, nonrotatably seated in the opening in the nose portion 22. The aforementioned collet 26 is secured against rotation Within the collet bushing 54 and a stepped shank portion 56 of the Wrapping bit 32 drivingly interfits with a mating recess opening to the forward end of the spindle 50. According to conventional practice, the bit sleeve 30 surrounds the bit 32 and is held in nonrotatable relation thereto by means of the collet nut 28 which secures the sleeve to the collet 26.

The aforementioned trigger 18 for switch 19 includes a depending portion 58 upon which digital pressure may be applied to pivot the trigger about a pivot pin 60 which is transversely carried between spaced legs 62 of the bearing support 40. As viewed in FIG. 4, the trigger 18 is urged into one limiting position by a coiled compression spring 64 seated between the trigger and the casing 10. The electrical circuit, not shown, between the battery means encased within housing 14 and the motor 38 includes the motor switch 19 having contacts 66 which close and open the circuit in response to pivotal movement of the switch trigger 18. It will be understood that the operator may digitally depress the trigger into the casing to pivot the trigger in a counterclockwise direction about pin 60 whereby a rearwardly extending lug 68, integrally formed with the trigger, will urge the lower contact 66 into engagement with the upper contact 66 thereby closing the electrical circuit between the battery means and the motor 38. Upon release of the trigger, the spring 64 biases the trigger for clockwise rotation about pin 60 thereby opening the contacts 66 and deenergizing the motor 38.

Upon energization of the motor 38, in the aforedescribed manner, the rotary drive of the motor shaft 44 will be transmitted to the wrapping bit 32 by the meshing gears 46 and 48 and the spindle 50. In response to bit rotation, a stripped portion 34a of the wire 34 will be withdrawn from a radially offset wire-receiving groove 70 and applied about the terminal in tightly wrapped convolutions. An insulated portion 34b of the wire 34 is seated in one of a pair of slots 72 relieved in the extreme forward end of the sleeve 30 to restrain the insulated portion 34b against rotation as the stripped portion 34a is wrapped about the terminal 36 by the rotative action of the bit. Upon completion of the wrapping operation, the motor 38 is deenergized and another conductor is manually positioned with respect to the bit 32 and sleeve 30 in the manner shown in FIG. 3. As stated above, it is desirable that the inertial rotation of the bit, following motor deenergization at the completion of each wrap, be arrested so that the bit assumes an indexed angular position known to the tool operator thereby to facilitate location of the wire-receiving groove 70 and insertion of a conductor 34 thereinto in a rapid and efficient manner. For the accomplishment of this object, the present invention provides an improved bit indexing mechanism 24 which is particularly well suited for a wire wrapping tool in which the size and weight of its component parts are limited by considerations of compactness and portability and by a limited available power supply for the tool.

Generally, indexing of the bit 32 is accomplished by coaction of an indexing member 74 with the aforementioned trigger 18 and spindle 50. The indexing member preferably, but not necessarily, comprises molded plastic and includes a cam plate 76 and an integral tapering extension 78. As best shown by FIG. 6, the cam plate has a spiral cam surface 80 formed about its outer perimeter and a radially opening notch 82 which intersects with the cam surface 80 to provide a shoulder 84. A segmental flange 86 projects rearwardly from the cam plate 76 toward the trigger 18 and in part defines the notch 82 and shoulder 84. The flange 86 also defines a stop surface 88 which, in a manner to be described, coacts with an abutting wall of a segmental lug 90 projecting forwardly from one side of the spur gear 48. An axial extension 92 of the spindle 50 coaxially penetrates a central opening through the indexing member 74 and rotatably journals the same. A coiled torsion spring 94 is loosely disposed about the spindle extension 92 and has bent over opposite ends fixedly attached within facing annular recesses 96 and 98 respectively defined in the cam plate 76 and the spur gear 48. The lefthand end of torsion spring 94 is fixedly inserted into a cylindrical recess 102 opening to the annular recess 96; and, the right-hand end of torsion spring 94 is received in a similar cylindrical recess, not shown, opening to the annular recess 98. The forward end of the upper surface of the trigger 18 is relieved, as shown in FIGS. 6 and 7, to provide an upwardly extending stop 100 which interfittingly engages with the aforementioned cam plate notch 82 when the trigger is in the released position, shown in FIG. 4 for releasably locking the indexing member 74 in the rotary position shown in FIG. 6.

The bit indexing action accomplished by the aforedescribed indexing mechanism 24 will be more clearly understood from the following description of the operation of the tool. Upon digital depression of the trigger 18, the contacts 66 of switch 19 are closed to energize the motor 38; and, at the same time, the stop 100 is pivoted downwardly out of the cam plate notch 82 to the phantom line position shown in FIG. 6 thereby releasing the indexing member 74 for rotation. Upon energization of motor 38 the spindle 50 is rotatably driven in a clockwise or forward direction, as indicated by the directional arrow in FIG. 6, through the gears 46 and 48 to effect working rotation of the wrapping bit 32. As viewed in FIG. 6, clockwise rotation of the spindle 50 produces clockwise or forward rotation of the indexing member 74 through the resilient driving connection effected by the torsion spring 94. As long as the motor 38 is energized, the indexing member 74 will rotate forwardly with the spindle 50 and without relative rotation therebetween under the urging of the torsion spring 94. Upon release of the trigger 18, following completion of a wire wrapping operation, the motor 38 will be deenergized and the trigger will be biased by the spring 64 to pivot the stop 100 upwardly into sliding engagement with the cam surface 80. Unless the stop 100 engages the shoulder 84 of the notch 82 immediately upon the release of the trigger 18, the inertial rotation of the rotating parts of the tool, i.e., the motor 38, the spindle 50 and the bit 32, will continue to drive the indexing member 74 through the torsion spring 92 in a clockwise direction. Such continued clockwise rotation after releasing the trigger will cause the cam surface to override the stop 100 until the shoulder 84 strikes the stop and, under the urging of the trigger spring 64, the stop seats fully within the notch 82 to arrest clockwise rotation of the indexing member 74. After the clockwise rotation of the indexing member 74 has been arrested by stop 100, the inertia of the motor 38, the spindle 50 and the bit 32 will continue to rotate the spindle and the attached bit in a clockwise direction relative to the arrested indexing member 74 thereby producing clockwise angular displacement of the segmental lug from the stop surface 88 which, as shown in FIG. 5, is disposed in the rotative path of the lug. Since the opposite ends of the torsion spring 92 are secured to the indexing member 74 and the spindle 50, respectively, such continued clockwise rotation of the spindle 50 with respect to the indexing member 74 will produce torsional loading of the torsion spring 94. Preferably the torsion spring 94 is adapted to completely absorb the inertial force of the rotating tool elements and to arrest the clockwise rotation of the same produced by such inertial force within less than a complete revolution of the spindle 50 and prior to the lugs striking the side of the flange 86 opposite the stop surface 88. After the clockwise rotation of the spindle 50 has been arrested by the loading of the torsion spring 94, the latter will act as a spring motor and will release the energy stored therein to produce counterclockwise or reverse indexing rotation of the spindle 50, the bit 32 and the motor 30. As the torsion springs 94 unwind, the counterclockwise rotation of the spindle 50 will carry the lug 90 into abutment with the stop surface 88, as shown in FIG. 5, to provide an indexed angular position for the spindle 50 and the attached bit 32. From the foregoing description of the indexing mechanism and its operation, it will be understood that the trigger 18 not only controls the motor 38, but also coacts with the indexing member 74 to define an indexed or home position for the bit 32. It will also be understood that inertial rotation of the tool parts, following deenergization of the motor 38, sequentially drives the indexing member in a clockwise direction to an arrested position, defining an indexed bit position, and

thereafter continues to rotate the spindle 50 in a clockwise direction to condition the torsion spring 94 for effecting counterclockwise indexing rotation of the bit 32.

An important object of this invention is accomplished by the provision of the above described bit indexing mechanism in which the novel construction and coaction of the component parts affords a substantial reduction in the size and number of parts over that required in known mechanisms intended for a like purpose. For example, while conventional indexing mechanism usually require some ratcheting means to drive the bit forwardly and to thereafter permit reverse indexing rotation of the bit, the present mechanism is adapted for retrograde rotation of the motor 38, the motor output gearing 46, 48 and the spindle 50, thereby eliminating the need for a declutching or ratchet means for disconnecting the motor from the bit during reverse bit indexing rotation.

Another advantage afforded by the present indexing mechanism is that the torsion spring 94 which drives the bit to an indexed position is positively loaded or coiled by the forward inertial rotation of the tool parts. This is in contradistinction to known indexing mechanisms employing torsion springs which are dependent for loading on frictional dragging engagement with a surrounding spindle cylinder, or the like, during the wire wrapping operation. Not only is such frictional loading uncertain and uneven, but wear due to frictional contact between relatively moving parts necessitates frequent tool servicing and part replacement.

It will be understood that the above description and accompanying drawings comprehend only general and preferred embodiments of the invention and that various changes in construction, proportion, material and arrangement of the elements thereof may be made without sacrificing any of the above enumerated advantages or departing from the scope of the appended claims.

What is claimed as new and useful is:

1. A rotary tool comprising:

a rotary spindle:

indexing means rotatively journaled on said spindle and cooperable with said spindle for defining an indexed angular position for the same;

first motor means having an energized condition and a deenergized condition and being operable for rotatively driving said spindle in the forward direction;

a second motor means drivingly connecting said spindle and said indexing means and being conditioned by the forward inertial rotation of said spindle and said first motor means, following deenergization of the latter, for rotatively driving said spindle in the reverse direction to said indexed angular position; and

said indexing means defining said indexed angular position as an incident to deenergization of said first motor means.

2. The invention defined in claim 1, wherein said second motor means comprises a spring disposed about said spindle and having opposite ends thereof fixedly attached to said spindle and said indexing means, respectively.

3. The invention defined in claim 1, wherein:

said first motor means is electrically operated and is provided with switch means for energizing and deenergizing the motor; and

said indexing means cooperates with an operating member for said switch means to define said indexed angular position when said operating member is operated to deenergize said first motor means.

4. The invention defined in claim 3, wherein said operating member and said indexing means are provided with interlocking surface means brought into interlocking engagement by forward inertial rotation of said spindle.

5. The invention according to claim 4, wherein said indexing means includes a cam plate having a notch relieved therein to receive the interlocking surface means of said operating member.

6. The invention according to claim 1, wherein said indexing means and said spindle are provided with interfering projections which are brought into abutment in response to reverse rotation of said spindle by said second motor means.

References Cited by the Examiner UNITED STATES PATENTS 2,649,121 8/1953 Reck -124 XR 2,649,122 8/ 1953 Mallina 2427 2,732,139 1/ 1956 Shaff 2427 2,826,920 3/1958 Barnes et al. 2427 2,927,741 3/ 1960 Moore et al. 140-122 CHARLES W. LANHAM, Primary Examiner.

WILLIAM F. PURDY, Examiner. 

1. A ROTARY TOOL COMPRISING: A ROTARY SPINDLE: INDEXING MEANS ROTATIVELY JOURNALED ON SAID SPINDLE AND COOPERABLE WITH SAID SPINDLE FOR DEFINING AN INDEXED ANGULAR POSITION FOR THE SAME; FIRST MOTOR MEANS HAVING AN ENERGIZED CONDITION AND A DEENERGIZED CONDITION AND BEING OPERABLE FOR ROTATIVELY DRIVING SAID SPINDLE IN THE FORWARD DIRECTION; A SECOND MOTOR MEANS DRIVINGLY CONNECTING SAID SPINDLE AND SAID INDEXING MEANS AND BEING CONDITIONED BY THE FORWARD INERTIAL ROTATION OF SAID SPINDLE AND SAID FIRST MOTOR MEANS, FOLLOWING DEENERGIZATION OF THE LATTER, FOR ROTATIVELY DRIVING SAID SPINDLE IN THE REVERSE DIRECTION TO SAID INDEXED ANGULAR POSITION; AND SAID INDEXING MEANS DEFINING SAID INDEXED ANGULAR POSITION AS AN INCIDENT TO DEENERGIZATION OF SAID FIRST MOTOR MEANS. 